CVE-2026-21998
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.0-8.0.45, 8.4.0-8.4.8 and 9.0.0-9.6.0. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
CVSS score
4.9
EPSS probability
%0.3
Risk score
0.0
Published
6 mo ago
Vulnerability Timeline (Change History)
CVE-2026-21998 historical changes made to the vulnerability by NVD, CISA and MITRE:
| Date | Actor / Source | Action / Description | Type | Previous value | New value |
|---|---|---|---|---|---|
| 16.10.2026 | nvd@nist.gov | Initial Analysis & CVSS Vector Assignment | CVSS V3.1 | — | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H |
| 14.04.2026 | CISA Coordinator | SSVC Risk Re-assessment | SSVC / KEV | exploitation: none | exploitation: none |
| 14.04.2026 | MITRE / NVD | New CVE Record Received & Ingested | CVE Created | — | CVE-2026-21998 |
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